There are many varieties of shaped products with a round profile. Products made of plastics (including composite ones) have seriously competed with traditional pipes made of metals. But, despite the universality of the use of polymer samples, in the conditions of laying routes outside buildings, when used in a number of pressure systems, there is no alternative to hardware. This article is about the features and characteristics of water and gas pipes (VGP).

Specifications for VGP are determined in years. Anyone who wants to understand the issue more thoroughly, it will be easy to do. But since the terminology and most of the parameters are incomprehensible to the average consumer (and therefore uninteresting), and some are not so significant, we will limit ourselves to only the main characteristics that are of practical importance during the installation and operation of a water supply or gas supply system.

Features of water and gas pipes

The material is high quality steel. Pipes can be without a protective coating or. The latter are used for the installation of structures (contours), the operation of which will take place in conditions of excessive humidity. All blanks are welded, which increases their strength.

The main advantages of water and gas pipes:

• Mechanical strength.
• Long service life.

It is allowed to have:

• Small dents that do not reduce Dy or wall thickness.
• Risk.
• Spot cleaning marks.
• Dross.

Signs of marriage

• Blisters on the tube.
• Cracks.
• Chips, scuffs on the end parts.
• Delamination of the coating on the "galvanization".

Characteristics of the VGP

The main linear parameters are in "mm".

1. Length (m): 4 - 12.

By agreement with the customer, in a batch of water and gas pipes, it is allowed to have off-gauge products not exceeding 5% of the total quantity (with a length of 1.5 - 4 m).

1. Dy: 6 - 150.

1. Dn: 10.2 - 165.

1. Wall thickness (limit): for light pipes (L) 1.8 - 4; ordinary (O) 2 - 4.5; reinforced (U) 2.5 - 5.5.

1. Maximum hydraulic pressure (MPa): categories L and O - 25, reinforced pipes - 32.

At the request of the customer - up to 50.

1. Weight 1 l.m. (kg): 0.37 - 15.88 (pipes L); 0.4 - 17.81 (O); 0.47 - 21.43 (U).

The mass of galvanized pipes is 3% higher than the value of a similar parameter for samples without a protective coating.

Deciphering the marking of VGP

Positions

1. Type of pipe: M - with a coupling, R - with a thread, C - with a zinc coating, P - increased accuracy, D - long thread, N - knurled.
2. Wall thickness.
3. Length (only measured).
4. GOST number.

Example 32 x 4 GOST 3262-75 - non-galvanized, random length, normal accuracy, Dy \u003d 32, wall \u003d 4. Ts-R-32 x 4 GOST-6000 3262-75 - the same product with thread, galvanized, measured length 6 m.

The use of water and gas pipes

Primary:

• In systems (circuits) of heating, hot water supply, cold water supply, gas supply.
• For pumping liquid and gaseous media in production.

Secondary:

Given the high cost of production, zealous owners often give VGP blanks a “second life”.

• Structural reinforcement elements.
• Sheds.
• Fencing.
• Jumpers and the like.

Price of steel pipes VGP

It depends on many factors, so it is appropriate to give only a few examples of the cost (in RUB/rm).

• 15 x 2.8 - within 56 (galvanization - 94).
• "Twenty" with the same wall - 74 (coated - 113).
• 57 x 3 - 187 (308).
• 76 x 3.5 - 212 (388).

The VGP pipe, the abbreviation in the name of which stands for "water and gas pipeline", is specially designed for laying water and gas communications. Even in our time, when modern manufacturers offer a huge range of pipes made from various materials, such specialized steel pipe products are very popular with construction and repair organizations, enterprises working in the housing and communal services sector.

You can get acquainted with all the requirements of GOST for steel VGP pipes by downloading this document in pdf format from the link below.

The relevance of using pipes of this category

The high popularity enjoyed by VGP pipes made of steel alloys is explained very simply. No matter how exceptional the characteristics of the pipes made of polymer materials that are popular today, their use in many cases is simply not possible. Such cases, in particular, include the installation of a pipeline in the open air, where it will be affected by a lot of negative factors.

It explains the demand for such products and the fact that, according to generally accepted requirements, pipelines for transporting gas and supplying it to consumers can only be made of steel pipes. That is why VGP pipes are simply an indispensable material in any gas industry.

How pipes are made

The main material from which pipes belonging to the VGP category are produced is carbon steel. The technological process of their manufacture consists of the following stages:

• first, steel blanks are prepared - strips, which are long metal strips with the required parameters in thickness and width;
• then a pipe is formed from the prepared strip, for which special equipment is used;
• the joint formed on the resulting product is welded using electric welding.

The quality characteristics that must be met by pipes of the VGP category manufactured using this technology are stipulated by the provisions of GOST 3262-75.

Taking into account the fact that pipes of this category are operated in rather difficult conditions, and very high requirements are imposed on the quality of the weld being created, the place of the formed joint is checked without fail using X-ray inspection methods.

The main influence on the service life of pipelines made of water and gas pipe products is exerted by their operating conditions, as well as the characteristics of the substance that is transported through them. This is explained by the fact that the transported substances have different chemical activity.

What to look for when choosing pipes

For the end user, who needs such steel pipes to solve specific problems, certain performance characteristics of these products are of interest, allowing them to be selected in the best way.

In order to make the right choice of such pipes and use them in accordance with the main purpose, it is important to understand the classification of products. The criteria by which such a classification is performed are stipulated by the provisions of GOST 3262-75.

Important criteria for sorting pipes of the VGP category are the material and method of their manufacture, as well as the method of their processing. So, depending on these parameters, pipes are distinguished:

• made of ferrous metal, the surface of which is not protected by anything;
• pipes, the surface of which is galvanized.

Tubular products, on the inner and outer surface of which a thin layer of zinc is applied, even outwardly differ from ordinary ones, as can be seen by comparing their photos. Such surface treatment of tubular products is necessary in order to reliably protect them from the aggressive effects of the external environment. Due to the chemical properties of this metal, pipes coated with a thin layer of zinc perfectly resist corrosion and can be successfully operated even in the most difficult conditions for a long period of time.

Important parameters of such pipes, regardless of whether they are galvanized or not, are their geometric dimensions: nominal bore, which is denoted by the abbreviation DU, as well as their wall thickness.

All geometric parameters of pipes of the VGP category, including their diameter, must comply with the requirements specified in GOST. All geometric dimensions of pipes produced by modern industry can be selected from the corresponding tables.

From the production conveyor, water and gas pipe products can be produced in two modifications:

• without thread;
• with a ready-made thread at both ends, which is applied by knurling or cutting.

Deciphering the numbers in the designation allows you to find out the exact diameter of the product. So, products in which their DU is marked with the number 50 (VGP DU50 pipe) have a diameter of two inches. And for pipes of the VGP category, in the designation of which there is DU25, the diameter is one inch. Accordingly, the marking of water and gas pipes contains their diameter in millimeters, and it will not be difficult to convert it to inches.

Classification of pipes according to their accuracy class

Water and gas pipes according to their accuracy classes are divided into two main categories.
The first includes tubular products of ordinary accuracy. In the production of products of this category, the following parameters are not standardized: the chemical composition of the material of manufacture, its mechanical characteristics. Pipes of this category are quite successfully used for arranging gas and water communications for domestic purposes.

The second category includes water and gas pipe products of increased accuracy. Galvanized pipes also belong to this category. From such pipes, in which both the chemical composition of the material of manufacture and its mechanical characteristics are normalized, parts of pipelines for industrial use are made with increased requirements for their reliability.

Extra options

For the convenience of those who are going to purchase water and gas pipes and use them for certain purposes, the length of such products is also standardized and may correspond to one of the following categories:

• interval 4–12 meters - measured length;
• the length of the pipes, a multiple of their measured value;
• unmeasured length, which, nevertheless, must be within the measured value.

Consumers of such products should keep in mind that the price for it is set not per unit length of the pipe, but per unit of its weight. It is also important to take into account the fact that the mass of galvanized pipes is 3% higher than the weight of products made from unprotected steel.

Steels from which galvanized and non-galvanized pipe products of increased accuracy are produced must comply with the requirements of GOST 1050, while the chemical composition and mechanical characteristics of the material of manufacture are not subject to rationing. Welds, with the help of which water and gas pipe products are connected after they are formed, must be of a reinforced type.

The range of water and gas pipe products made of black steel assumes their release with several options for wall thickness. Depending on this parameter, such products are:

• light class;
• ordinary category;
• reinforced type.

The wall thickness of such products, which, in accordance with the assortment, can be selected from the table, is normalized by the requirements of GOST 3262-75. On the basis of this regulatory document, an assortment of pipe products is formed; it also stipulates a number of other parameters that such products must comply with: nominal bore, outer diameter, theoretical mass of one running meter.

Pipes of various classes are designed for operation under various operating pressures. So, pipes corresponding to the light category can be operated at a pressure not exceeding 25 kgf / cm2, and products of a reinforced type - 32 kgf / cm2.

At the request of the customer of a batch of water and gas pipes, long or short threads can be applied to their ends. Tubular products of galvanized type can be supplied to customers not only with threads, but also equipped with couplings for their installation.

Electrowelded water and gas pipes

Water and gas pipe products made using welded joints are successfully used for the installation of pipelines through which both liquid and gaseous media are transported. For the production of such pipes, steel grades are used that are well connected by welding: 10, 20, 3SP, 3PS. Depending on the purpose and operating conditions of the pipeline, for the installation of which such products will be used, they can be additionally subjected to heat treatment after manufacture.

The measured length of such products is in the range of 9–11.7 meters, and the unmeasured length, which should be within the measured length, is 4–11 m.

Permissible deviations in the dimensions of water and gas pipes depend on the length and diameter of the product. So, if there is a preliminary agreement with the customer of a batch of pipes, the following deviations are allowed in their geometric parameters:

• 5% - for pipes whose length is in the range of 1.5–4 meters;
• for galvanized pipe products, where the threads are applied at the ends using the knurling technology, a diameter reduction of 10% is allowed over the entire area of ​​​​its location.

There is a generally accepted method for calculating the weight of a pipe, where the density of the steel from which it is made is taken as 7.85 g / cm3. As mentioned above, the weight of galvanized pipe products is assumed to be 3% more than the weight of ordinary ones.

This standard applies to non-galvanized and galvanized steel welded pipes with threaded or knurled cylindrical threads and without threads used for water and gas pipelines, heating systems, as well as for parts of water and gas pipeline structures.

Designation:	GOST 3262-75*
Russian name:	Pipes steel water and gas. Specifications
Status:	current
Replaces:	GOST 3262-62
Text update date:	01.10.2008
Date added to database:	01.02.2009
Date of entry into force:	01.01.1977
Designed by:	USSR Ministry of Ferrous Metallurgy
Approved:	USSR State Committee for Standards (09/11/1975)
Published:	Standards Publishing House No. 1994

STEEL PIPES

SPECIFICATIONS

GOST 3262-75

STANDARDS PUBLISHING HOUSE

Moscow

STATE STANDARD OF THE UNION OF THE SSR

the dateintroductions 01.01.77

This standard applies to non-galvanized and galvanized steel welded pipes with cut or knurled cylindrical threads and without threads used for water and gas pipelines, heating systems, as well as for parts of water and gas pipeline structures.

1. ASSORTMENT

1.1. Pipes are made according to the dimensions and weight given in Table. one.

At the request of the consumer, light series pipes intended for thread rolling are manufactured according to the mass dimensions given in Table. 2.

(Changed edition, Rev. No. 1 , 3 ).

1.2. The length of the pipe is made from 4 to 12 m:

measured or multiple measured length with an allowance for each cut of 5 mm and a maximum deviation for the entire length plus 10 mm;

unmeasured length.

By agreement between the manufacturer and the consumer, up to 5% of pipes with a length of 1.5 to 4 m are allowed in a batch of off-gauge pipes.

Table 1

Dimensions, mm

Conditional pass	Outside diameter	Pipe Wall Thickness			Weight of 1 m of pipes, kg
			ordinary	enhanced		ordinary	enhanced

table 2

Dimensions, mm

Conditional pass	Outside diameter	Wall thickness	Weight of 1 m of pipes, kg

Notes:

1. For a thread made by knurling, a reduction in its internal diameter of up to 10% along the entire length of the thread is allowed on the pipe.

2. The mass of 1 m of pipes was calculated with a steel density of 7.85 g / cm 3. Galvanized pipes are 3% heavier than non-galvanized ones.

1.3. Limit deviations in pipe dimensions should not exceed those indicated in Table. 3.

Table 3

Pipe dimensions	Limit deviations for manufacturing precision pipes
		elevated
Outer diameter with nominal bore:
up to 40 mm incl.
	- 0,5
Outer diameter with nominal bore: over 40 mm
	- 1,0
Wall thickness	- 15 %	- 10 %

Notes :

1. The maximum deviation in the plus side along the wall thickness is limited by the maximum deviations in the mass of pipes.

2. Pipes of the usual manufacturing accuracy are used for water supply, gas pipelines and system heating. Pipes of increased manufacturing accuracy are used for parts of water and gas pipeline structures.

1.4. Maximum deviations in the mass of pipes should not exceed + 8%.

At the request of the consumer, the maximum deviations in mass should not exceed:

7.5% - for the party;

10% - for a single pipe.

(Changed edition, Rev. No. 2, 5).

1.5. The curvature of pipes per 1 m of length should not exceed:

2 mm - with nominal bore up to 20 mm inclusive;

1.5 mm - with nominal bore over 20 mm.

1.6. Pipe threads can be long or short. Thread requirements must comply with those specified in Table. 4.

Table4

Conditional passage, mm		Thread length to the run, mm		Conditional passage, mm	Number of threads with conditional passage	Thread length to the run, mm
			short				short

1.7. Pipes with a nominal bore of 6, 8, 10, 15 and 20 mm are wound into coils at the request of the consumer.

Legend examples

Ordinary pipe, not galvanized, of the usual manufacturing accuracy, random length, with a nominal bore of 20 mm, a wall thickness of 2.8 mm, without thread and without a coupling:

Trumpet 20´ 2.8 GOST 3262-75

The same with the clutch:

Pipe M-20´ 2.8 GOST 3262-75

The same, measured length, threaded:

Pipe R-20´ 2.8 - 4000 GOST 3262-75

The same, zinc coated, random length, threaded:

Pipe Ts-R-20´ 2.8 GOST 3262-75

The same, with zinc coating, measured length, threaded:

Pipe Ts-R-20´ 2.8 - 4000 GOST 3262-75

For pipes for thread rolling, the letter H is indicated after the word "pipe" in the symbol.

For pipes with a long thread, the letter D is indicated after the word "pipe" in the symbol.

For pipes of increased manufacturing accuracy, the letter P is indicated in the symbol after the nominal bore size.

(Revised edition, Rev. No. 1).

2. TECHNICAL REQUIREMENTS

2.1. Pipes are manufactured in accordance with the requirements of this standard and according to technological regulations approved in the prescribed manner, from steels according to GOST 380 and GOST 1050 without standardization of mechanical properties and chemical composition.

Pipes for parts of water supply and gas pipeline structures are made of steel according to GOST 1050.

2.2. At the request of the consumer, the ends of pipes to be welded with a wall thickness of 5 mm or more must be chamfered at an angle of 35-40 ° to the end of the pipe. At the same time, an end ring with a width of 1 - 3 mm should be left.

At the request of the consumer, on ordinary and reinforced pipes with a nominal bore of more than 10 mm, the thread is applied to both ends of the pipe.

2.1; 2.2. (Changed edition, Rev. No. 3, 4).

2.3. At the request of the consumer, the pipes are equipped with couplings made in accordance with GOST8944, GOST8954, GOST8965 and GOST8966 at the rate of one coupling for each pipe.

(Revised edition, Rev. No. 3).

2.4. Cracks, captivity, swelling and sunsets are not allowed on the surface of the pipes.

Laminations are not allowed at the ends of the pipes.

Separate dents, ripples, risks, traces of stripping and other defects due to the production method are allowed, if they do not take the wall thickness beyond the minimum dimensions, as well as a scale layer that does not interfere with inspection.

On pipes made by furnace welding, it is allowed to reduce the outer diameter to 0.5 mm at the weld site if there is a gentle thickening of the inner diameter of not more than 1.0 mm in this place.

(Changed edition, Rev. No. 3, 4).

2.5. At the request of the consumer, on pipes with a nominal bore of 20 mm or more, on the inner surface of the pipe seam, the burr must be cut or flattened, while the height of the burr or its traces should not exceed 0.5 mm.

At the request of the consumer, on pipes with a nominal bore of more than 15 mm, made by the method of furnace welding and the method of hot reduction, a gentle thickening of a height of not more than 0.5 mm is allowed on the inner surface of the pipes in the weld zone.

(Changed edition, Rev. No. 2, 3, 4, 5, 6).

2.6. Pipe ends must be cut square. The value of the bevel of the end is allowed no more than 2 ° . Burr residue must not exceed 0.5 mm. When removing burrs, the formation of blunting (rounding) of the ends is allowed. It is allowed to cut pipes in the line of the mill.

By agreement between the manufacturer and the consumer, burrs up to 1 mm are allowed on pipes with a nominal bore of 6-25 mm, made by furnace welding.

(Changed edition, Rev. No. 4, 6).

2.7. Galvanized pipes must have a continuous zinc coating over the entire surface with a thickness of at least 30 microns. The absence of zinc coating on the ends and threads of pipes is allowed.

On the surface of galvanized pipes, blistering and foreign inclusions (hardzinc, oxides, sintered charge), peeling of the coating from the base metal are not allowed.

Separate flux spots and traces of pipe capture by lifting devices, roughness and slight local zinc deposits are allowed.

It is allowed to correct individual non-galvanized sections by 0.5% of the outer surface of the pipe in accordance with GOST 9.307.

(Changed edition, Rev. No. 3, 4).

2.8. Pipes must withstand hydraulic pressure:

2.4 MPa (25 kgf / cm 2) - pipes, ordinary and light;

3.1 MPa (32 kgf / cm 2) - reinforced pipes.

At the request of the consumer, the pipes must withstand a hydraulic pressure of 4.9 MPa (50 kgf / cm 2)

2.9. Pipes with a nominal bore up to 40 mm inclusive must withstand a bend test around a mandrel with a radius equal to 2.5 of the outer diameter, and with a nominal bore of 50 mm - on a mandrel with a radius equal to 3.5 of the outer diameter.

At the request of the consumer, the pipes must withstand the expansion test:

for pipes with conditional passage from 15 to 50 mm - not less than 7%;

for pipes with a nominal bore of 65 or more - at least 4%.

At the request of the consumer, the pipes must withstand the flattening test up to a distance between the flattened surfaces equal to 2/3 of the outer diameter of the pipes.

2.8,2.9. (Changed edition, Rev. No. 2, 3, 5).

2.10. At the request of the consumer, the mechanical properties of pipes for parts of water and gas pipeline structures must comply with GOST 1050.

2.11. The pipe thread must be clean, free of flaws and burrs and comply with GOST 6357, accuracy class B.

Pipes with cylindrical threads are used when assembling with seals.

2.10; 2.11. (Changed edition, Rev. No. 3, 4).

2.12. In the place of the seam, blackness on the threads of the thread is allowed if the decrease in the normal height of the thread profile does not exceed 15%, and at the request of the consumer does not exceed 10%.

Threads with broken (for cut) or incomplete (for knurled) threads are allowed on threads, provided that their total length does not exceed 10% of the required thread length, and at the request of the consumer does not exceed 5%.

2.13. It is allowed on the thread to reduce the useful length of the thread (without run-off) up to 15% compared to that specified in, and at the request of the consumer up to 10%.

2.12.,2.13. (Changed edition, Rev. No. 2, 3, 5).

2.14. Threading galvanized pipes is carried out after galvanizing.

2.15. (Deleted, Rev. No. 3).

2.16. At the request of the consumer, welded seams of pipes are subjected to control by non-destructive methods.

(Revised edition, Rev. No. 5).

3. ACCEPTANCE RULES

3.1. Pipes are accepted in batches. The batch must consist of pipes of the same size, of the same brand and be accompanied by one quality document in accordance with GOST 10692 with an addition for pipes intended for the manufacture of parts for water and gas pipeline structures, made of steel according to GOST1050: chemical composition and mechanical properties of steel in accordance with the document on the quality of the blank manufacturer.

The mass of the party is not more than 60 tons.

(Changed edition, Rev. No. 3, 4).

3.2. Surface, dimensions and curvature are checked for each pipe of the batch.

It is allowed to use statistical control methods according to GOST 18242 with a normal level. Control plans are established by agreement between the manufacturer and the consumer.

The control of the outer diameter of the pipes is carried out at a distance of at least 15 mm from the end of the pipe.

(Changed edition, Rev. No. 3, 4, 5).

3.3. To control the parameters of the thread, to test for expansion, flattening, bending, the height of the internal burr, burr residue, right angle and chamfer angle (for pipes with beveled edges), mechanical properties, no more than 1%, but not less than two pipes from the batch, are selected, and for pipes made by continuous furnace welding - two pipes per batch.

(Changed edition, Rev. No. 3, 4).

3.4. All pipes are subjected to mass control.

(Revised edition, Rev. No. 3).

3.5. Each pipe is subjected to a hydraulic pressure test. With 100% quality control of the weld by non-destructive methods, hydraulic pressure testing may not be carried out. At the same time, the ability of the pipes to withstand the test hydraulic pressure is guaranteed.

(Revised edition, Rev. No. 6).

3.6. To check the thickness of the zinc coating on the outer surface and in accessible places on the inner surface, two pipes are taken from the lot.

(Revised edition, Rev. No. 2).

3.7. If unsatisfactory test results are obtained for at least one of the indicators, a second test is carried out on a double sample.

The results of repeated tests apply to the entire batch.

4. TEST METHODS

4.1. For quality control, one sample is cut from each selected pipe for each type of test.

The tensile test is carried out according to GOST 10006. Instead of the tensile test, it is allowed to control the mechanical properties by non-destructive methods.

4.2. Inspection of the surface of the pipes is carried out visually.

4.3. Hydraulic testing is carried out according to GOST 3845 with exposure under test pressure for at least 5 s.

4.4. The bend test is carried out according to GOST 3728. Galvanized pipes are tested before coating.

(Revised edition, Rev. No. 3).

4.4a. The expansion test is carried out according to GOST 8694 on a conical mandrel with a taper angle of 6 ° .

It is allowed to test on a mandrel with a taper angle of 30 ° .

(Changed edition, Rev. No. 3, 4).

4.4b. The flattening test is carried out according to GOST 8695.

(Revised edition, Rev. No. 3).

4.4c. Weld seam control is carried out by non-destructive methods according to normative and technical documentation.

(Introduced additionally, Rev. No. 3).

4.5. The thickness of the zinc coating on the outer surface and in accessible places on the inner surface is controlled in accordance with GOST 9.301 and GOST 9.302, as well as with devices of the MT-41NTs, MTZON or Impulse types according to the regulatory and technical documentation.

4.6. The thread is checked with threaded ring gauges according to GOST 2533 (third class of accuracy).

In this case, the screwing-in of the non-going ring gauge on the thread should be no more than three turns.

(Changed edition, Rev. No. 3, 4).

4.7. The curvature of the pipes is controlled by a straightedge in accordance with GOST 8026 and a set of probes according to ND.

(Changed edition, Rev. No. 3, 5).

4.8. The right angle of the ends of the pipes is controlled by a square 90 ° size 160´ 100 mm class 3 GOST 3749, plate probes of set 4 according to ND or goniometer GOST 5378. The bevel angle is controlled by a goniometer according to GOST 5378.

(Changed edition, Rev. No. 3, 6).

4.9. The control of the outer diameter is carried out with smooth micrometers in accordance with GOST 6507, gauges-brackets in accordance with GOST 2216 or GOST 18360.

The wall thickness, the height of the internal burr and the height of the burrs are measured with a micrometer according to GOST 6507-90 or a wall gauge according to GOST 11358 from both ends of the pipe.

The length of the pipes is measured with a tape measure according to GOST 7502. The thread is controlled by gauges according to GOST 2533.

Control of the mass of a batch of pipes is carried out on scales of not more than 10 tons with a division value of not more than 20 kg.

(Changed edition, Rev. No. 3, 4, 5, 6).

4.10. Weld seam control is carried out by non-destructive methods according to technical documentation.

(Introduced additionally, Rev. No. 4).

5. MARKING, PACKAGING, TRANSPORT AND STORAGE

5.1. Marking, packaging, transportation and storage are carried out in accordance with GOST 10692 with an addition.

5.1.1. The pipe thread must be protected from mechanical damage and corrosion by lubricant according to the normative and technical documentation.

Sec. 5. (Revised edition, Rev. No. 3).

INFORMATION DATA

1. DEVELOPED AND INTRODUCED by the Ministry of Ferrous Metallurgy of the USSR

DEVELOPERS

V. I. Strzhok, cand. tech. Sciences, V. M. Vorona, Ph.D. tech. Sciences, Yu. M. Mironov, cand. tech. nook, A. I. Postolova

2. APPROVED AND INTRODUCED BY Decree of the USSR State Committee for Standards dated 09/11/75 No. 2379

3. Periodicity of inspection 5 years

4. REPLACE GOST3262-62

5. REFERENCE REGULATIONS AND TECHNICAL DOCUMENTS

	Item number
GOST 9.301-86
GOST 9.302-88
GOST 9.307-89
GOST 380- 94
GOST 1050-88
GOST 2216-84
GOST 2533-88
GOST 3728-78
GOST 3749-77
GOST 3845-75
GOST 5378-88
GOST 6357-81
GOST 6507-90
GOST 7502-89
GOST 8026-92
GOST 8694-75
GOST 8695-75
GOST 8944-75
GOST 8954-75
GOST 8965-75
GOST 8966-75
GOST 10006-80
GOST 10692-80
GOST 11358-89
GOST 18242-72
GOST 18360-9 3

6. The validity period was removed by the Decree of the State Standard of November 12, 1991 No. 1726

7. Reprinted with Amendments No. 1, 2, 3, 4, 5, 6, approved in November 1977, December 1978, January 1987, May 1988, November 1989, November 1991 (IUS 1 -78.2-79, 4-87, 8-88, 2-90, 2-92)

Supports for pipelines in polyurethane foam insulation

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Pipeline support prices add up

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• Pumps
• Grundfos
• A pump is a device that moves gases or liquids. In these modern conditions, life without pumping equipment is simply impossible to imagine, this is confirmed by the fact that 20% of the world's electricity is used to operate pumping equipment. Pumps are divided into domestic and industrial, depending on the scope of application. Household pumps are used in the heating, sewerage and water supply systems, while industrial pumps are used in cooling systems, industrial water supply, water treatment, supply and pumping of liquids that are supplied under high pressure.

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• This section presents expansion membrane tanks, which serve as a reservoir for pumps and accumulators. When you choose a tank for a heating system, you need to pay attention to the membrane material, which must be durable and not collapse when exposed to aggressive media and high temperatures. Particular attention should be paid to the working conditions and the main purpose of the expansion tank in the system. The products presented in this section are certified by the most successful companies that specialize in the production of these products.

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• Steel and cast iron pipe fittings have been used for threaded connections of highways and devices since the beginning of the use of a metal pipe to move the working medium, therefore, even in our time, it is all the more difficult to overestimate the importance of these connecting elements. Pipes and fittings have always been the basis of any pipeline, therefore, with the development of technical progress developed technologies and types of steel and cast iron fittings. The price of manufacturing a fitting depends on the materials used, their weight and purpose. A cast-iron fitting is made by casting and installed for branching, turns, pipe transitions to a different diameter, especially in cases where periodic disassembly of connections is necessary. The steel fitting acts more as a welded threaded connector, as well as couplings and locknuts on the spurs, and is produced mainly from a pipe billet on lathes. Most of the hydraulic devices such as heaters, filters, distributors, automatic and control devices, etc. it is impossible to manufacture and connect to the pipeline without the use of a steel and cast iron fitting.

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• In the catalog of our products there are cast-iron styles and pipes VChShG - socket and floor which are made of high-strength nodular cast iron with a nominal diameter of 80, 100, 125, 150, 200, 250, 300, 350, 400, 500, 600, 700, 800, 900, 1000 mm. Ductile iron pipes are made 6 meters long, under a sealing rubber ring, with an external and internal coating that complies with the standards of GOST R ISO 2531, EN 545. Socket pipes with such types of connections as: TYTON, TYTON sewage and RVS (RJ) are on sale. Tyton (Tyton) - socket connection for a sealing ring with a working pressure of 3.0-6.4 MPa; RVS (RJ) - a socket-and-lock connection for a sealing rubber ring with a working pressure of 2.5-8.8 MPa; Ductile iron with nodular graphite - ductile iron has differences from lamellar graphite gray iron such as higher strength, which is close to the properties of mild steel, and higher resistance to cracking. To obtain such properties, ductile iron was obtained by modifying liquid iron with magnesium and various additives. As a result, a metal was obtained in which graphite is in the form of balls, which makes it possible to increase the plasticity and strength of pipes and styles.

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Categories of OKS in expanded form

Classifier OKPD 2

search code OKPD 2 online, all categories of the classifier

Conventions

File Icons and Document Properties- GOST icon;

File types

- the document is represented by a set of scanned images; - the document can be downloaded as one PDF file, the file consists of unrecognized scanned pages; - the document can be downloaded as one PDF file with recognized text; - the document can be downloaded as one PDF file, links to other GOSTs work inside the file, the text is recognized

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GOST 3262-75 Steel water and gas pipes. Specifications

Categories GOST 3262-75 for OKS:

• 23.40. Pipelines and their components
• 23.40.10 Cast iron and steel pipes *Steel pipes and tubes for special purposes, see 77.140.75

Document status: valid, put into effect on 01/01/1977 Title in English: Water-supply and gas-supply steel pipes. Specifications Date of updating information according to the standard: 09/11/2019 at 10:56 am (less than 3 months ago) Type of standard: Standards for products (services) GOST start date: 1977-01-01 Date of last edition of the document: 2007-05-01

Document codes GOST 3262-75:

OKP code: 138500;138501 KGS code: B62 OKSTU code: 1385

Number of pages: 8

Purpose of GOST 3262-75: This standard applies to non-galvanized and galvanized steel welded pipes with threaded or knurled cylindrical threads and without threads used for water and gas pipelines, heating systems, as well as for parts of water and gas pipeline structures

SRNTI index(es): 534731 The document was developed by the organization: Minchermet of the USSR Document keywords: tests, acceptance, assortment, technical requirements, non-galvanized pipes, galvanized pipes, welded pipes, steel pipes Links to others: TU 2-034-225-88

You can download GOST 3262-75 in the following versions:

Date added in file version:

Amendments and changes to GOST 3262-75:

Name, type:

registrations:

start action:

Change No. 1 to GOST 3262-75

change type: Text change
Change number: 1
Registration number: 2669


Change No. 2 to GOST 3262-75

change type: Text change
Change number: 2
Registration number: 45


Change No. 3 to GOST 3262-75

change type: Text change; Title changed
Change number: 3
Registration number: 4456
New value: See title


Change No. 4 to GOST 3262-75

change type: Text change
Change number: 4
Registration number: 1139
New value: -


Change No. 5 to GOST 3262-75

change type: Text change
Change number: 5
Registration number: 3347
New value: -


Change No. 6 to GOST 3262-75

change type: Text change
Change number: 6
Registration number: 1726
New value: -

GOST 3262-75

Group B62

INTERSTATE STANDARD

STEEL WATER AND GAS PIPES

Specifications

Water-supply and gas-supply steel pipes. Specifications

OKP 13 8500, OKP 13 8501

Introduction date 1977-01-01

INFORMATION DATA

1. DEVELOPED AND INTRODUCED by the Ministry of Ferrous Metallurgy of the USSR

DEVELOPERS

V.I.Struzhok, Ph.D. tech. sciences; V.M.Vorona, Ph.D. tech. sciences; Yu.M.Mironov, Ph.D. tech. sciences; A.I. Postolova

2. APPROVED AND INTRODUCED BY Decree of the USSR State Committee for Standards dated 11.09.75 N 2379

3. Periodicity of inspection - 5 years

4. REPLACE GOST 3262-62

5. REFERENCE REGULATIONS AND TECHNICAL DOCUMENTS

	Item number

________________
* Valid on the territory of the Russian Federation.

6. The limitation of the validity period was removed by the Decree of the State Standard of November 12, 1991 N 1726

7. EDITION with Changes N 1, 2, 3, 4, 5, 6, approved in November 1977, December 1978, January 1987, May 1988, November 1989, November 1991 ( IUS 1-78, 2-79, 4-87, 8-88, 2-90, 2-92)

This standard applies to non-galvanized and galvanized steel welded pipes with threaded or knurled cylindrical threads and without threads used for water and gas pipelines, heating systems, as well as for parts of water and gas pipeline structures.

(Changed edition, Rev. N 2, 3, 5).

1. ASSORTMENT

1.1. Pipes are made according to the dimensions and weight given in table.1.

Table 1

Dimensions, mm

Conditional pass	Outside diameter	Pipe Wall Thickness			Weight of 1 m of pipes, kg
		lungs	ordinary	enhanced	lungs	ordinary	enhanced

At the request of the consumer, light series pipes intended for thread rolling are manufactured according to the dimensions and weight given in Table 2.

table 2

Dimensions, mm

Conditional pass	Outside diameter	Wall thickness	Weight of 1 m of pipes, kg

Notes:

1. For a thread made by knurling, a reduction in its inner diameter of up to 10% along the entire length of the thread is allowed on the pipe.

2. The mass of 1 m of pipes is calculated with a steel density of 7.85 g/cm. Galvanized pipes are 3% heavier than non-galvanized ones.

(Changed edition, Rev. N 1, 3).

1.2. The length of the pipe is made from 4 to 12 m:

Measured or multiple measured length with an allowance for each cut of 5 mm and a longitudinal deviation for the entire length plus 10 mm;

Unmeasured length.

By agreement between the manufacturer and the consumer, up to 5% of pipes with a length of 1.5 to 4 m are allowed in a batch of off-gauge pipes.

1.3. Limit deviations in pipe dimensions should not exceed those indicated in Table 3.

Table 3

Pipe size	Limit deviation for precision pipes manufacturing
		elevated
Outer diameter with nominal bore:
up to 40 mm incl.	0.4mm -0,5
over 40 mm	0,8% -1,0
Wall thickness

Notes:

1. The maximum deviation in the plus side along the wall thickness is limited by the maximum deviations in the mass of pipes.

2. Pipes of ordinary manufacturing accuracy are used for water pipes, gas pipelines and heating systems. Pipes of increased manufacturing accuracy are used for parts of water and gas pipeline structures.

1.4. Maximum deviations in the mass of pipes should not exceed + 8%.

At the request of the consumer, the maximum deviations in mass should not exceed:

7.5% - for the party;

10% - for a single pipe.

(Changed edition, Rev. N 2, 5).

1.5. The curvature of pipes per 1 m of length should not exceed:

2 mm - with nominal bore up to 20 mm inclusive;

1.5 mm - with nominal bore over 20 mm.

1.6. Pipe threads can be long or short. Thread requirements must be as specified in Table 4.

Table 4

Conditional passage, mm	Number of threads with conditional passage	Thread length to the run, mm
			short

1.7. Pipes with a nominal bore of 6, 8, 10.15 and 20 mm are wound into coils at the request of the consumer.

Legend Examples

Ordinary pipe, non-galvanized, of the usual manufacturing accuracy, random length, with a nominal bore of 20 mm, a wall thickness of 2.8 mm, without thread and without a coupling:

Pipe 20x2.8 GOST 3262-75

The same with the clutch:

Pipe M-20x2.8 GOST 3262-75

The same, measured length, threaded:

Pipe P-20x2.8-4000 GOST 3262-75

The same, zinc coated, random length, threaded:

Pipe Ts-R-20x2.8 GOST 3262-75

The same, with zinc coating, measured length, with thread:

Pipe Ts-R-20x2.8-4000 GOST 3262-75

For pipes for thread rolling, the letter H is indicated after the word "pipe" in the symbol.

For pipes with a long thread, the letter D is indicated after the word "pipe" in the symbol.

For pipes of increased manufacturing accuracy, the letter P is indicated in the symbol after the nominal bore size.

(Changed edition, Rev. N 1).

2. TECHNICAL REQUIREMENTS

2.1. Pipes are manufactured in accordance with the requirements of this standard and according to the technological regulations approved in the prescribed manner, from steels with and without standardization of mechanical properties and chemical composition.

Pipes for parts of water and gas pipeline structures are made of steel according to GOST 1050.

2.2. At the request of the consumer, at the ends of pipes to be welded, with a wall thickness of 5 mm or more, chamfers must be removed at an angle of 35-40 ° to the end of the pipe. In this case, an end ring with a width of 1-3 mm should be left.

At the request of the consumer, on ordinary and reinforced pipes with a nominal bore of more than 10 mm, the thread is applied to both ends of the pipe.

2.1, 2.2. (Changed edition, Rev. N 3, 4).

2.3. At the request of the consumer, the pipes are equipped with couplings made according to, and, at the rate of one coupling for each pipe.

(Changed edition, Rev. N 3).

2.4. Cracks, captivity, swelling and sunsets are not allowed on the surface of the pipes.

At the ends of the pipes, delamination is not allowed.

Separate dents, ripples, risks, traces of stripping and other defects due to the production method are allowed, if they do not take the wall thickness beyond the minimum dimensions, as well as a scale layer that does not interfere with inspection.

On pipes made by furnace welding, it is allowed to reduce the outer diameter to 0.5 mm at the weld site if there is a gentle thickening of the inner diameter of not more than 1.0 mm in this place.

(Changed edition, Rev. N 3, 4).

2.5. At the request of the consumer, on pipes with a nominal bore of 20 mm or more, on the inner surface of the pipe seam, the burr must be cut or flattened, while the height of the burr or its traces should not exceed 0.5 mm.

At the request of the consumer, on pipes with a nominal bore of more than 15 mm, made by the method of furnace welding and the method of hot reduction, a gentle thickening of a height of not more than 0.5 mm is allowed on the inner surface of the pipes in the weld zone.

(Changed edition, Rev. N 2, 3, 4, 5, 6).

2.6. Pipe ends must be cut square. The value of the bevel of the end is allowed no more than 2 °. Burr residues should not exceed 0.5 mm. When removing burrs, the formation of blunting (rounding) of the ends is allowed. It is allowed to cut pipes in the mill line.

By agreement between the manufacturer and the consumer, burrs up to 1 mm are allowed on pipes with a nominal bore of 6-25 mm, made by furnace welding.

(Changed edition, Rev. N 4, 6).

2.7. Galvanized pipes must have a continuous zinc coating over the entire surface with a thickness of at least 30 microns. The absence of zinc coating on the ends and threads of pipes is allowed.

On the surface of galvanized pipes, blistering and foreign inclusions (hardzinc, oxides, sintered charge), peeling of the coating from the base metal are not allowed.

Separate flux spots and traces of pipes being caught by lifting devices, roughness and slight local zinc deposits are allowed.

It is allowed to correct individual non-galvanized sections by 0.5% of the outer surface of the pipe in accordance with GOST 9.307.

(Changed edition, Rev. N 3, 4).

2.8. Pipes must withstand hydraulic pressure:

2.4 MPa (25 kgf / cm) - ordinary and light pipes;

3.1 MPa (32 kgf/cm) - reinforced pipes.

At the request of the consumer, the pipes must withstand a hydraulic pressure of 4.9 MPa (50 kgf/cm).

2.9. Pipes with a nominal bore up to 40 mm inclusive must withstand a bend test around a mandrel with a radius equal to 2.5 of the outer diameter, and with a nominal bore of 50 mm - on a mandrel with a radius equal to 3.5 of the outer diameter.

At the request of the consumer, the pipes must withstand the expansion test:

For pipes with nominal bore from 15 to 50 mm - not less than 7%;

For pipes with a nominal bore of 65 mm or more - at least 4%.

At the request of the consumer, the pipes must withstand the flattening test up to a distance between flattened surfaces equal to 2/3 of the outer diameter of the pipes.

2.8, 2.9. (Changed edition, Rev. N 2, 3, 5).

2.10. At the request of the consumer, the mechanical properties of pipes for parts of water and gas pipeline structures must comply with GOST 1050.

2.11. Pipe threads must be clean, free of flaws and burrs and comply with accuracy class B.

Pipes with cylindrical threads are used when assembling with seals.

2.10, 2.11. (Changed edition, Rev. N 3, 4).

2.12. In the place of the seam, blackness is allowed on the threads of the thread, if the decrease in the normal height of the thread profile does not exceed 15%, and at the request of the consumer does not exceed 10%.

Threads with stripped (for cut) or incomplete (for knurled) threads are allowed on threads, provided that their total length does not exceed 10% of the required thread length, and at the request of the consumer does not exceed 5%.

2.13. It is allowed on the thread to reduce the useful length of the thread (without run-off) up to 15% compared to that indicated in Table 4, and at the request of the consumer - up to 10%.

2.12, 2.13. (Changed edition, Rev. N 2, 3, 5).

2.14. Threading on galvanized pipes is carried out after galvanizing.

2.15. (Deleted, Rev. N 3).

2.16. At the request of the consumer, welded seams of pipes are subjected to control by non-destructive methods.

(Changed edition, Rev. N 5).

3. ACCEPTANCE RULES

3.1. Pipes are accepted in batches. The batch must consist of pipes of the same size, the same steel grade and be accompanied by one quality document in accordance with the addendum for pipes intended for the manufacture of parts for water and gas pipeline structures, from steel according to; chemical composition and mechanical properties of steel - in accordance with the document on the quality of the enterprise - the manufacturer of the workpiece.

Party weight - no more than 60 tons.

(Changed edition, Rev. N 3, 4).

3.2. The surface, dimensions and curvature are checked for each pipe of the batch.

It is allowed to apply statistical control methods with a normal level. Control plans are established by agreement between the manufacturer and the consumer.

The control of the outer diameter of the pipes is carried out at a distance of at least 15 mm from the end of the pipe.

(Changed edition, Rev. N 3, 4, 5).

3.3. To control the parameters of the thread, to test for expansion, flattening, bending, the height of the internal burr, burr residues, right angle and chamfer angle (for pipes with bevelled edges), mechanical properties are selected no more than 1%, but not less than two pipes from the batch, and for pipes manufactured by continuous furnace welding, two pipes per lot.

(Changed edition, Rev. N 3, 4).

3.4. All pipes are subjected to mass control.

(Changed edition, Rev. N 3).

3.5. Each pipe is subjected to a hydraulic pressure test. With 100% quality control of the weld by non-destructive methods, hydraulic pressure testing may not be carried out. At the same time, the ability of the pipes to withstand the test hydraulic pressure is guaranteed.

(Changed edition, Rev. N 6).

3.6. To check the thickness of the zinc coating on the outer surface and in accessible places on the inner surface, two pipes are taken from the batch.

(Changed edition, Rev. N 2).

3.7. Upon receipt of unsatisfactory test results for at least one of the indicators, it is repeated tests on a double sample.

The retest results apply to the entire lot.

4. TEST METHODS

4.1. For quality control, one sample is cut from each selected pipe for each type of test.

The tensile test is carried out in accordance with GOST 10006. Instead of the tensile test, it is allowed to control the mechanical properties by non-destructive methods.

4.2. Inspection of the surface of the pipes is carried out visually.

4.3. The hydraulic test is carried out with exposure under test pressure for at least 5 s.

4.4. The bend test is carried out according to GOST 3728. Galvanized pipes are tested before coating.

(Changed edition, Rev. N 3).

4.4a. The expansion test is carried out on a conical mandrel with a taper angle of 6°.

The test can be carried out on a mandrel with a taper angle of 30°.

(Changed edition, Rev. N 3, 4).

4.4b. The flattening test is carried out according to GOST 8695.

(Changed edition, Rev. N 3).

4.4c. Weld seam control is carried out by non-destructive methods according to normative documentation.

(Introduced additionally, Rev. N 3).

4.5. The thickness of the zinc coating on the outer surface and in accessible places on the inner surface is controlled by and , as well as by devices of the MT-41NTs, MTZON or Impulse types according to regulatory documentation.

4.6. The thread is checked with threaded ring gauges according to (third accuracy class).

In this case, the screwing of the non-going gauge-ring on the thread should be no more than three turns.

(Changed edition, Rev. N 3, 4).

4.7. The curvature of the pipes is controlled by a straightedge along and a set of probes according to ND.

(Changed edition, Rev. N 3, 5).

4.8. The right angle of the ends of the pipes is controlled by a 90 ° square with a size of 160x100 mm of class 3 according to, lamellar probes of set 4 according to ND or a goniometer according to GOST 5378. The bevel angle of the chamfer is controlled by a goniometer according to GOST 5378.

(Changed edition, Rev. N 3, 6).

4.9. The control of the outer diameter is carried out with smooth micrometers according to, staple gauges according to or GOST 18360.

The wall thickness, the height of the internal burr and the height of the burrs are measured with a micrometer along or a wall gauge along at both ends of the pipe.

The length of the pipes is measured with a tape measure in accordance with GOST 7502. The thread is controlled with gauges in accordance with GOST 2533.

The control of the mass of a batch of pipes is carried out on scales of not more than 10 tons with a division value of not more than 20 kg.

(Changed edition, Rev. N 3, 4, 5, 6).

4.10. Weld seam control is carried out by non-destructive methods according to technical documentation.

(Introduced additionally, Rev. N 4).

5. MARKING, PACKAGING, TRANSPORT AND STORAGE

5.1. Marking, packaging, transportation and storage are carried out according to the supplement.

5.1.1. Pipe threads must be protected from mechanical damage and corrosion by grease in accordance with regulatory documents.

Section 5. (Changed edition, Rev. N 3).

The text of the document is verified by:
official publication
Pipes metal and connecting parts to them.
Part 3. Welded pipes. Profile pipes: Sat. GOSTs. -
M.: IPK Standards Publishing House, 2001